Real Time Math Simulation of Contact Interaction during Spacecraft Docking and Berthing

Contact reactions of guide surfaces of assembly interfaces lead to the decreasing of theirs lateral and angular misalignments. The focus of this paper is the development of algorithms for computation of guide surfaces contact forces with acceptable engineering accuracy for real time simulation of assembly operations. Therefore, each complex guide surface is described as a set of contacting elements. Each contacting element for one＇s part can be represented by a finite set of geometric primitives which geometry is described by low order algebraic equations. So contact conditions and geometric parameters for all pairs of primitives are determined by analytical expressions. Math models are developed for two classes of contact interaction. The first class includes all cases when each contacting surface has several degrees of freedom of motion. Therefore, contact reactions introduced into differential equations of motion are calculated by using contacting elements penetrations, stiffness and damping parameters. The second class corresponds to all cases when one of contacting surfaces has insignificant inertia and only one degree of freedom of relative displacement counteracted by a spring. Here contact reactions are calculated from spring tension with any practical accuracy. This is very useful in some practical applications. Presented algorithms provide real time simulation together with some approaches for reduction of redundant comnutations.

Parallel Sensing in Metaverses: Virtual-Real Interactive Smart Systems for “6S” Sensing

In the construction of Metaverses,sensors that are referred to as the“bridge of information transmission”,play a key role.The functionality and efficiency of today’s sensors,which operate in a manner similar to physical sensing,are frequently constrained by their hardware and software.In this research,we proposed the Parallel Sensing framework,which includes background,concept,basic methods and typical application of parallel sensing.In our formulation,sensors are redefined as the integration of real physical sensors and virtual software-defined sensors based on parallel intelligence,in order to boost the performance of the sensors.Each sensor will have a parallel counterpart in the virtual world within the framework of parallel sensing.Digital sensors serve as the brain of sensors and maintain the same properties as physical sensors.Parallel sensing allows physical sensors to operate in discrete time periods to conserve energy,while cloud-based descriptive,predictive,and prescriptive sensors operate continuously to offer compensation data and serve as guardians.To better illustrate parallel sensing concept,we show some example applications of parallel sensing such as parallel vision,parallel point cloud and parallel light fields,both of which are designed by construct virtual sensors to extend small real data to virtual big data and then boost the performance of perception models.Experimental results demonstrate the effective of parallel sensing framework.The interaction between the real and virtual worlds enables sensors to operate actively,allowing them to intelligently adapt to various scenarios and ultimately attain the goal of“Cognitive,Parallel,Crypto,Federated,Social and Ecologic”6S sensing.

Study on the mechanism of interaction for coal and methane gas

Although two moulds for methane gas in coal with the free state and adsorption state have been popularly considered, the derivation between the real methane gas state equation in coal and the perfect gas state equation has been fuzzily considered and the mechanism of interaction for coal aromatics and methane gas molecules has not been understood. Then these problems have been discussed in this paper applied the principle of statistical thermo mechanics and quantum chemistry as well as based on the numerical calculating of experiential data in quantum chemistry. Therefore, it is revealed by research results that the experience state equation for real methane gas in coal, which is put forward in this paper, is closer to actual situation and the interaction process for methane gas adsorption on the surface of coal aromatics can be formulated by Morse potential function. Furthermore it is most stable through this research that the structural mould for methane gas molecule adsorption on the surface of coal nuclear with one gas molecule on top of another aromatics in regular triangle cone has been understood, and it is a physical adsorption for methane gas adsorption with single layer molecule on the surface of coal nuclear.

基于实时交互式音视频信息系统的临床实践教学模式在心内科本科教学中应用探讨

目的探讨基于实时交互式音视频信息系统(video information system,VIS)的临床实践教学模式在心内科本科教学中的应用。方法选取2022年在大连医科大学附属第一医院心内科实习的5年制临床医学专业53名学生作为研究对象,根据班别随机分为对照组(n=25)和试验组(n=28)。对照组采取传统教学法,试验组采用基于VIS的临床实践教学方法。结合临床实践的客观结构化考核和问卷调查情况,比较两组学生出科考核成绩、教学模式及教学效果满意度。结果试验组学生采用VIS教学后的心内科出科考核成绩高于对照组[(86.20±1.92)分vs.(92.54±0.99)分,P=0.001];试验组学生教学模式满意度调查中“很满意”者的比例较高(85.7%)。结论基于实时交互式音视频信息系统的心血管内科临床实践教学模式能有效提升实践教学效果。

组态式智能家居人机交互系统的设计与实现

智能家居的人机交互系统影响用户体验,而传统的菜单式的交互页面存在着画面固定、操作不直观等问题,并且系统通用性较差,实时性也不高。针对上述问题,本文开发了一种基于云平台的组态式智能家居人机交互系统,设计了包括页面、数据和交互控制组件在内的组件,以此为基础实现了图形化的界面构建。针对智能家居设备数据多源异构的特点,采用MongoDB和Redis相结合的存储方案进行分类存储,并以Redis+WebSocket的方式实现数据的实时推送。实验表明,系统功能正确,可实现智能场景搭建、设备交互,实时更新设备数据及统计能耗。

矿井排水监控数字孪生系统研究与实现

常规的矿井排水监控系统面临可视化程度差、联动性不足以及动态环境下矿井排水的实时监控方式单调等问题,结合数字孪生技术,开发了矿井排水监控数字孪生系统。通过数字空间、虚实交互层结构框架和立体可视化系统数据架构的构建,结合流体力学,利用Unity3D开发引擎和五维模型思想,构建矿井排水立体可视化系统架构,实现了实时监控、故障预警以及虚实混合控制等多种应用功能。通过实验验证了矿井排水监控数字孪生系统的可行性,为数字孪生技术在煤炭领域的应用提供了解决方案。

元宇宙环境中虚实交互数据故事的生成路径

基于元宇宙视角研究虚实交互数据故事的技术方案与生成路径,对于充分发挥数据故事的沉浸式交互体验和虚实场景下的融合共享功能至关重要。文章分析元宇宙与数据故事在故事要素、交互方式、虚实内容等方面的交互融合,从政策制度、实现技术和融合路径层面出发,基于“用户层架构”构建元宇宙环境下七层次的虚实交互数据故事生成框架,对国内外开展元宇宙研究的典型企业进行案例分析。国内外企业在虚实交互数据故事的生成路径中存在技术创新、个性化用户体验、平台的开放性和互操作性、多业务场景覆盖等方面的共性,未来应构建“真实业务数据”与“沉浸式虚拟环境”相结合的、对现实世界产生实际影响的“故事化元宇宙”。

建筑施工工艺仿真实训教学基地教学研究

在新时代产教融合模式下,目前建筑产业发展急需数字化新型人才,同时结合教育发展趋势和教育相关政策,基于多媒体技术的智能型教学平台被越来越多的教育工作者熟知和运用,尤以建筑施工工艺仿真实训教学基地提供的信息技术在授课中的应用,达到教与学的智慧虚实交互,对于传统课堂来说是一场颠覆性的革命。

基于CAN总线的农用汽车信息交互系统设计

随着现代农业对高效、精准作业需求的日益增加,传统农用车辆的信息传输方式存在数据延迟、通信不稳定以及模块间信息难以集成等缺陷,无法满足现代农业机械化和智能化发展的需求。该文提出了一种基于CAN总线的农用汽车信息交互系统,通过控制模块、传感器模块、信息显示模块和报警模块之间的数据交互,实现车辆状态的实时监测和高效信息传输,该系统能够显著提高农用汽车的作业效率和安全性,为推动智慧农业的发展提供了技术支撑。

数字经济与实体经济的协调耦合发展及其交互影响

在数字经济蓬勃发展背景下,如何更好地促进数字经济与实体经济的深度融合发展是一个极具现实意义的研究命题。选取中国2011—2021年城市数据,分析数字经济与实体经济间的协调耦合关系,并使用面板联立方程模型对二者间的交互影响进行实证检验。研究结果表明:(1)我国数字经济与实体经济的协调耦合度呈现上升趋势,且表现为东高西低、以城市群为核心辐射区、以省会城市为关键辐射点的发展格局;(2)同一城市内数字经济和实体经济间可以产生显著的交互作用,其中数字经济所产生的赋能作用更强;(3)进一步利用广义空间三阶段最小二乘法(GS3SLS)通过构建空间面板联立方程模型发现,数字经济和实体经济的交互影响不仅存在同一城市内,还会通过空间作用对邻近城市产生显著的正向外溢效应。

Real life efficacy and safety of direct-acting antiviral therapy for treatment of patients infected with hepatitis C virus genotypes 1, 2and 3 in northwest China

BACKGROUND Regimens involving direct-acting antiviral agents(DAAs)are recommended for the treatment of infection with hepatitis C virus(HCV)genotypes 1,2 and 3.But real-world data is still not enough,especially in Asia.AIM To investigate the efficacy and safety of DAA-based regimens in a real-life setting in China.METHODS This study included 366 patients infected with HCV genotypes 1,2 and 3,with or without cirrhosis,who were observed between May 2015 and December 2018.They were treated with ledipasvir and sofosbuvir(SOF)(genotype 1)with or without ribavirin(RBV),SOF and RBV(genotype 2),or SOF and daclatasvir(genotype 3),with or without RBV,for 12 or more wk.The participants’sustained virological responses(SVR)at post-treatment week 12(SVR12)was the primary endpoint.The occurrence of adverse events and drug-drug interactions were recorded.RESULTS In the 366 patients,genotype 1(59.0%)was the most common genotype,followed by genotypes 2(34.4%)and 3(6.6%).Liver cirrhosis was diagnosed in 154(42.1%)patients.Fifty(13.7%)patients were treatment-experienced.Intention-to-treat analysis revealed that SVR12 was 86.3%(316/366).For modified intention-totreat analysis,SVR12 was achieved in 96.6%of overall patients(316/327),96.3%in patients with genotype 1,97.5%in those with genotype 2,and 95.0%in those with genotype 3.Most of the treatment failures were due to lack of follow-up(3cases had non-responses,1 had virological breakthrough,11 relapsed and 36 did not participate in the follow-up).There was no significant difference in SVR between different genotypes and liver statuses(P<0.05).Patients with lower alanine aminotransferase levels at baseline who achieved an end of treatment response were more likely to achieve SVR12(P<0.05).High SVR was observed regardless of age,gender,liver status,alpha-fetoprotein,HCV RNA levels or history of antiviral therapy(P>0.05 for all).The cumulative hepatocellular carcinoma occurrence and recurrence rate after using the DAAs was 0.9%.Most of the adverse events were mild.We found two cases of special adverse events.One case involved facial and bilateral lower extremity edema,and the other case showed an interesting change in lipid levels while on medication.No severe adverse events were noted.CONCLUSION The DAA-based regimens tested in this study have excellent effectiveness and safety in all patients infected with HCV genotypes 1,2 and 3,including those with cirrhosis.

Range of applicability of real mode superposition approximation method for seismic response calculation of non-classically damped industrial buildings

An industrial building is a non-classically damped system due to the different damping properties of the primary structure and equipment.The objective of this paper is to quantify the range of applicability of the real model superposition approximation method to the seismic response calculation of industrial buildings.The analysis using lumped mass-and-shear spring models indicates that for the equipment-to-structure frequency ratiosγf>1.1 orγf<0.9,the non-classical damping effect is limited,and the real mode superposition approximation method provides accurate estimates.For 0.9<γf<1.1,the system may have a pair of closely spaced frequency modes,and the non-zero off-diagonal damping terms have a non-negligible effect on the damping ratios and mode shape vectors of these modes.For 0.9<γf<1.1 and the equipment-to-structure mass ratiosγm<0.07,the real mode superposition approximation method results in large errors,while the approximation method can provide an accurate estimation for 0.9<γf<1.1 andγm>0.07.Furthermore,extensive parametric analyses are conducted,where both steel structures and reinforced concrete structures with equipment with various damping ratios are considered.Finally,the finite element analysis of a five-story industrial building is adopted to validate the proposed range of applicability.

基于NXMCD的虚实映射实验交互系统设计与实践

该文基于数字孪生理念,结合NX MCD机电概念设计、PLC编程与控制和LabVIEW的图形化编程手段,完成了基于NX MCD的虚实映射实验交互系统设计与实践。以LabVIEW设计的UI界面为控制监测端,物理对象与MCD虚拟模型为执行端,实现了物理对象与MCD虚拟模型的虚实映射,同时MCD虚拟模型能够输出控制信号进而控制物理对象。在此基础上,设计了步进电机往复运动与MCD虚拟模型虚实映射实验案例。该实验案例可为本科生和研究生相关课程的实践教学提供虚实映射交互实验方法和手段,可显著提升学生的创新实践能力与水平,是对数字化实践教学研究的一次探索。

电力动态碳排放责任因子

新型电力系统建设背景下,需要充分发挥海量用电终端具有的储能和灵活用电资源来解决电力系统的实时调节需求,这一调节目标的实现亟需建立合理的引导指标和激励机制。为此,该文提出利用“电力动态碳排放责任因子”激励用电终端进行自律式调节的方法。首先,给出这种方法的基本原则;然后,具体讨论碳排放责任因子的计算方法,再利用电网的实际运行数据说明这种确定电力动态碳排放责任因子方法的有效性和可持续性;最后,通过案例分析建筑等用电终端的灵活性调节潜力。该文提出的电力动态碳排放责任因子,为新型电力系统实现与海量用户侧灵活可调资源间的实时互动提供了新的思路,未来将进一步完善其政策、理论及实际实施等多方面的工作。

基于时空交叉感知的实时动作检测方法

时空动作检测依赖于视频空间信息与时间信息的学习.目前,最先进的基于卷积神经网络(Convolutionsl Neural Networks,CNN)的动作检测器采用2D CNN或3D CNN架构,取得了显著的效果.然而,由于网络结构的复杂性与时空信息感知的原因,这些方法通常采用非实时、离线的方式.时空动作检测主要的挑战在于设计高效的检测网络架构,并能有效地感知融合时空特征.考虑到上述问题,本文提出了一种基于时空交叉感知的实时动作检测方法.该方法首先通过对输入视频进行乱序重排来增强时序信息,针对仅使用2D或3D骨干网络无法有效对时空特征进行建模,提出了基于时空交叉感知的多分支特征提取网络.针对单一尺度时空特征描述性不足,提出一个多尺度注意力网络来学习长期的时间依赖和空间上下文信息.针对时序和空间两种不同来源特征的融合,提出了一种新的运动显著性增强融合策略,对时空信息进行编码交叉映射,引导时序特征和空间特征之间的融合,突出更具辨别力的时空特征表示.最后,基于帧级检测器结果在线计算动作关联性链接.本文提出的方法在两个时空动作数据集UCF101-24和JHMDB-21上分别达到了84.71%和78.4%的准确率,优于现有最先进的方法,并达到73帧/秒的速度.此外,针对JHMDB-21数据集存在高类间相似性与难样本数据易于混淆等问题,本文提出了基于动作表示的关键帧光流动作检测方法,避免了冗余光流的产生,进一步提升了动作检测准确率.

减速器虚实交互AR装配系统设计研究

针对目前虚拟装配系统交互性差、操作感不强等问题,基于增强现实技术研发一种虚实交互AR装配系统。以减速器拆装为例,结合碰撞器与分离轴定理设计的模型间碰撞检测方法,减少在线计算工作量,可实现快速动态装配仿真;基于图像识别提出的触发式脱卡识别方法,解决了传统脱卡识别过程中虚拟模型位置不可控的问题。实验结果表明,该系统不仅能够实现实时虚实交互的装配仿真,而且增强了装配的交互性和操作感。

基于数字孪生的装备维修保障平台

维修保障是装备运行使用的重要部分,装备的维修保障能力直接影响其效能的发挥。而基于历史故障数据的传统维修保障方式很难实现实时精确保障,使得装备效能发挥受到了影响。数字孪生技术的发展为装备运行使用过程中的全资可视化、装备状态实时感知、故障快速预测并诊断、维修方案智能化制定及验证、维修指导以及按需训练培训等提供了良好的实现条件。文中在研究装备维修保障对象、业务领域及寿命期保障内容的基础上,设计一种装备维修保障数字孪生模型,分析装备数字孪生体组成以及需要管理的元素;在分析装备维修保障孪生数据流的基础上,提出了装备维修保障数字孪生平台框架;最后针对装备维修保障数字孪生体的构建及使用,分析了数字孪生平台实现的关键技术。研究成果可指导装备维修保障数字孪生体建设工作的开展,实现装备实时、精确保障。

应用于机床加工的总线数字量模块开发与试验研究

为了满足数控机床加工对信号量数据采集传输的实时性和稳定性的应用需求,如机床加工现场的轴运动位移硬件限位信号、气阀水阀信号、刀具测量等信号,同时能与可编程控制器建立通信进行数据交互,可实现信号量检测与控制功能。文章设计并开发基于以太网通讯技术的EtherCAT通信协议的数字量模块,对数字量模块软硬件设计内容与数据交互程序的执行流程进行研究,并通过配合标准EtherCAT通信主站TwinCAT进行试验,证明开发的数字量模块能与控制器主站正常建立通信并进行数据传输,且与EtherCAT总线通信数据周期保持同步。基于数字量信号检测设计出机床刀径测量方案,应用该数字量模块在机床加工中进行量刀试验,结果表明通过数字量模块对检测信号的实时响应计算得到的机床刀具磨损误差满足应用要求,具有工程实际价值,达到了研究的目的。

基于数据流模型的航线网络结构可视分析方法

针对航线网络结构多维属性关联分析问题,提出一种基于数据流模型的多视图协同网络结构可视分析方法。引入数据流模型,增强多维数据分析时的交互和多视图协同效果;构建基于数据流模型的航线网络结构可视分析系统用于方法验证。该方法对比和实验结果表明,利用航线网络数据流实时交互和多视图协同分析网络结构数据,完成聚类、相关性、异常值分析任务,能更好地分析数据之间的关联关系,有助于理解航线网络的结构和特征。最后,通过以上方法分析网络结构特点与不足,提出航线网络优化建议,能更好地帮助用户完成可视分析任务,探索数据分布特征、发现多维数据之间的关联关系。

虚拟仿真联合近实时网络交互提升来华留学生急诊技能

目的:探讨虚拟仿真联合近实时网络交互是否可以有效提高留学生急诊技能水平。方法:选取安徽医科大学60名来华攻读医学全科学士(MBBS)留学生作为研究对象,将其随机分为实验组和对照组,每组各30人。实验组学生接受为期4周的虚拟仿真技术与近实时网络交互相结合的技能技能培训,对照组学生接受为期4周的虚拟仿真技术的急诊技能培训。观察两组学生在急诊技能评估中的数据,主要指标包括急诊技能的准确性、合理性和人文关怀得分,次要指标包括自信心、学习主动性和参与度。结果:实验组学生急诊技能准确性、人文关怀、自信心、参与度平均得分高于对照组,差异有计统计学意义(t=2.08、3.93、2.97、2.52,P<0.05);两组学生急诊技能合理性、学习主动性平均得分比较,差异无统计学意义(t=0.92、1.10,P>0.05)。结论:虚拟仿真联合近实时网络交互可以有效提高留学生的急诊技能水平,有望成为急诊医学教育的有效辅助工具。